DETECTION STATISTICS OF DEEP LEVELS IN MINORITY-CARRIER TRANSIENT SPECTROSCOPY

A theoretical treatment of the minority carrier transient spectroscopy (MCTS) experiment is presented. We have modeled the minority carrier flux through the depletion region of an illuminated Schottky diode hel d under reverse bias, and used these data to calculate the occupancy o f minority carrier traps as a function of energy, capture cross sectio n, and temperature. The model shows that the capacitance transient mon itored in the MCTS experiment decreases in intensity as the temperatur e is raised. It is demonstrated that this causes inaccuracies in the m easured deep level activation energy E(a) derived from an Arrhenius pl ot of the data. Simulated MCTS spectra have been compared with measure d MCTS spectra of hole emission from the gold donor in silicon, and ve ry good agreement between modeled and experimental spectra is observed . The model explains the commonly observed phenomenon of a reduction i n MCTS peak heights for increasing temperature, which is the opposite effect from that commonly observed in conventional deep level transien t spectroscopy data. It is shown that the correct choice of rate windo w can significantly reduce errors in the measured value of E(a). (C) 1 997 American Institute of Physics.